Patent GB-777010-A (GB)
Title: A process for the production of unsaturated carbonylic compounds
IPC: B01J23/86
Filed: 1955-07-21
Abstract: Unsaturated aldehydes or ketones containing an olefinic linkage between two carbon atoms of aliphatic character, one of which is linked directly to the carbon atom of the carbonyl group, are obtained by a process comprising oxidizing an olefinic hydrocarbon, having at least three carbon atoms in the molecule, with oxygen or an oxygen-containing gas in the presence of a cuprous oxide-containing catalyst at an elevated temperature and in the presence of a promoter consisting of one or more of the following: iodine, bromine, hydrogen iodide, hydrogen bromide and the iodo- or bromo-substituted aliphatic hydrocarbons.  Suitable olefinic compounds are, for example, propylene, butene-1, butene-2, isobutylene, di-isobutylene, pentene-1, pentene-2, 3-methyl-butene-1, 2-methyl-butene-2, hexene-1, hexene-2, 4-methyl-pentene-1, 3.3-dimethyl-butene-1, 4-methyl-pentene-2, octene-1, cyclopentene, cyclohexene and 3-methyl cyclohexene. Mixtures containing olefines with saturated organic compounds may be oxidized, the saturated compounds present acting as diluents. The cuprous oxide catalyst is preferably supported on or mixed with a carrier material, e.g. silica gel, silicon carbide porous aggregates, pumice, bauxite, activated aluminas, activated carbon, silica-alumina and magnesia.  Materials which are gaseous under the conditions of the process, e.g. nitrogen, steam and paraffins, may be used as diluents.  The preferred temperature of the reaction is between 200 DEG  and 450 DEG  C.  Suitable iodo- and bromo-substituted hydrocarbons for use as promoters are, for example, iodomethane, bromomethane, iodoethane, bromethane, vinyl iodide and bromide, allyl iodide and bromide, 1- and 2-iodopropane, di-iodopropane, butyl iodides, amyl iodides, bromo propanes, butyl bromides, amyl bromides, crotonyl iodide and their homologues.  The process may be used for the conversion of propylene to acrolein, isobutylene to methacrolein, a - and b -butylene to methyl vinyl ketone, pentene-1 or pentene-2 to ethyl vinyl ketone and/or pentene-3-one-2, 2-methyl-butene-2 to methyl isopropenyl ketone and cyclopentene to cyclopentanone-2. In an example propylene is oxidized with an oxygen-containing gas in the presence of a catalyst comprising copper oxide and alundum with small amounts of iodine, isopropyl iodide and dibromopropane as promoters to give acrolein.ALSO:Catalysts for the production of unsaturated aldehydes and ketones by the oxidation of olefinic hydrocarbons comprise cuprous oxide and a promoter consisting of one or more of the following:-iodine, bromine, hydrogen iodide, hydrogen bromide and iodo- or bromo-substituted aliphatic hydrocarbons.  The cuprous oxide may be supported on or mixed with a carrier material, such as silica gel, silicon carbide porous aggregates, pumice, bauxite, activated aluminas, "Aloxite" (Registered Trade Mark), activated carbon, silica-alumina and magnesia.  The supported cuprous oxide catalysts may be prepared, for example, by treating the degassed carrier with a concentrated aqueous solution of cupric nitrate, cupric chloride or copper ammonium nitrate, drying the resulting impregnated material, heating it at 250-400 DEG C. in a stream of air and reducing the cupric oxide thus formed to cuprous oxide with hydrogen.  Suitable iodo-and bromo-substituted hydrocarbons for use as promoters are iodo- and bromo-methane and ethane, vinyl iodide and bromide, allyl iodide and bromide, iodo-propanes, butyl iodides, amyl iodides, bromopropanes, butyl bromides, amyl bromides, crotonyl iodide and their homologues.  The promoters may be introduced into the reaction zone by direct addition to the olefinic feed, to the oxygen or into the catalyst bed as a solid, as a solution or as a suspension in a liquid, gas or vapour.  In an example propylene is oxidized by oxygen to acrolein using cuprous oxide and alundin as a catalyst with iodine, isopropyl iodide and dibromopropane as activators.